ISOLATION AND CHARACTERIZATION OF Pb-RESISTANT STRAINS AND THE REMOVAL OF Pb(II)

摘要

A total of 48 strains of lead-resistant bacteria were isolated from Meiliang bay of the Taihu Lake, China, and were tested for Pb(II) resistance. The strain THKPS16 with the maximum growth value under Pb(II) stress was regarded as the optimal strain for further study. The partial sequences were amplified from the strain and the BLAST query revealed that it was closely related to Acinetobacter sp., and it was by 98% homologously to Acinetobacter oleivorans strain DR1 and Acinetobacter calcoaceticus strain NCCB 22016. Batch experiments were conducted to remove Pb(II) using the Acinetobacter sp., and the effects of the initial Pb(II) concentration, pH, and temperature conditions on Pb(II) removal efficiency were investigated. The results showed that the Acinetobacter sp. could successfully remove Pb(II) ions, and the removal efficiency decreased with the increase of initial Pb(II) concentration. The removal efficiency of Pb(II) was highest at pH 5 and 35 degrees C, and the removal efficiency rates were 71.2% and 75.1% under 100 mg/L Pb(II) stress. The SEM and FTIR analysis indicated that the Acinetobacter sp. cells were irregular, and cracked with the appearance of wrinkles on the surface after Pb(II) stress, and the functional groups involved in the interaction with lead were ionizable functional groups that included amino, carboxyl, and hydroxyl groups.